Impact of Hypertension Duration on the Cardiovascular Benefit of Intensive Blood Pressure Control

BACKGROUND: The optimal timing for initiating intensive systolic blood pressure (SBP) treatment remains unclear. While longer hypertension duration is positively associated with increased cardiovascular disease risk, it is unknown whether patients with prolonged hypertension can derive similar benefits from intensive SBP treatment. METHODS: From the STEP trial (Strategy of Blood Pressure Intervention in the Elderly Hypertensive Patients), 8442 participants with complete hypertension duration data were categorized by hypertension duration <= 5 years, 5 to 10 years, 10 to 15 years, and >15 years. The primary outcome was a composite of cardiovascular events. Hazard ratios were calculated using the Fine-Gray subdistribution hazard model. RESULTS: The incidences of the primary outcome increased significantly in patients with hypertension over 15 years than those <5 years in the standard SBP treatment group (adjusted hazard ratios, 1.68 [95% CI, 1.11-2.56]) but not in the intensive treatment group. Each 1-year increase in hypertension duration continuously increased the adjusted risk of major cardiovascular events by 4% (95% CI, 1.01-1.08) up to 20 years, plateauing at an adjusted hazard ratio of 2.27 (95% CI, 1.28-4.04). After intensive SBP treatment, the incidences of major cardiovascular events were similar across different hypertension duration groups, which were 2.22%, 1.69%, 3.02%, and 2.52%, respectively (P>0.05). Subgroup analyses indicated a potential sex difference in this relationship between hypertension duration and the primary outcome in the standard SBP treatment group (P-interaction=0.05). CONCLUSIONS: Initiating intensive SBP treatment at any stage of hypertension duration could reduce cardiovascular disease risk to a comparable level.